1. Field of the Invention
The present invention relates to hour meters for recording the operating time of monitored engines, and more particularly to an improved engine operating time recording apparatus having operating power completely derived from an internal magneto-type electrical generator of a monitored engine.
2. Description of the Prior Art
Hour meters are commonly used to measure the running or operating time of various equipment for scheduling preventive maintenance. Disadvantages of known mechanical hour meters include the imprecise recording of time and unreliability. Other known hour meters for recording the operating time of monitored engines utilize a battery direct current (DC) source, as is available in many vehicles such as automobiles. Alternatively known hour meters use an alternating current (AC) source. However, an AC source or a battery is not included with many small engine applications, such as in lawn mowers or pumps.
In small engine applications, typically an electronic ignition control system is used in conjunction with an internal magneto-type electrical generator of the engine. For example, the ignition control system can be operatively positioned adjacent a flywheel of the engine being controlled. The ignition control system provides a high voltage, such as in a secondary winding of an ignition coil, to fire a spark plug or spark plugs associated with the engine. Typically the engine flywheel carries a permanent magnet that energizes a stator core of the ignition control system upon rotation of the flywheel for generating various electrical control pulses.
It is desirable to provide an hour meter for recording the operating time of small engines that is completely powered by an internal magneto-type electrical generator of a monitored engine and that is reliable and accurate.